Potato diseases and control. Potatoes: diseases and pests

Potatoes grow well in almost any climatic conditions. It also tolerates acidic soil, but the yield is significantly increased after liming. A large amount of moisture and light are, in fact, the only conditions for the growth of potatoes. But even under ideal conditions, the culture is under the threat of infection with fungi, viruses and bacteria. Here we will consider the most basic problems and universal solutions that will help not only cope with the presented examples, but also prevent many other similar diseases. Despite the fact that potato varieties are resistant to late blight, nematode or scab, diseases and pests still continue to destroy the crop. But for every enemy there is a weapon.

Potato diseases and control

A large number of diverse enemies of potatoes significantly reduces the level of the crop. These include not only fungi and insects, but also viruses that infect tubers and inflorescences and prevent normal growth. Because of this, it is very important to carry out a variety of preventive measures before planting and during cultivation to preserve your potatoes. Diseases and pests inflict huge damage, so it's better to invest and rid yourself of the experience than to lose half of the crop.

The use of poisons and chemicals reduces the nutritional quality of potatoes, it can become harmful and dangerous not only for beneficial insects, animals and birds, but also for humans. Potato diseases and fighting with them require special attention before planting. Let's consider in detail all their types in this material. For more complete assimilation of information in the article there are photos of diseases of potatoes, as well as pests parasitizing on tubers.

Wireworm

A wireworm is a larva of a click beetle. It is a small gray insect 12-15 mm in length. He got the name because he makes a clicking sound, turning from his back to his paws. One female lays between 50 and 200 eggs in the spring, from which the ill-fated wireworm appears. Larvae are able to destroy a whole crop, so first of all it is necessary to protect it from the beetles themselves.

Fighting the Wireworm

There are three ways that are suitable for fighting this parasite:

1. Peeled potatoes are stringed on a stick and buried in the ground about 7 centimeters. It is better to make several such potatoes to cover a large area. The larva of the click beetle will gather on it, and in four days it will be possible to dig it out. Destroy the pests can be with the help of boiling water or fire.
2. When planting potatoes, pour into the ground sunflower oil with finely chopped shell from chicken eggs. Such a solution will kill the wireworm before it reaches the potatoes. This method will help the harvest not only from the wireworm, many other earth insects die in such a solution, for example, a bear.
3. For two weeks before planting, dig into the ground corn kernels - about 2-3 nests per square meter. The wireworm attracts not only potatoes, larvae with pleasure will gather around the grains. When the corn sprouts, it can be unearthed, the larvae can be robbed and burned or poured with boiling water.

Late blight

Phytophthora (phytophthora) is not only the cause of the loss of tomato crops, but also the most common diseases of potatoes, and the fight against them is important for all farmers, regardless of the cultivated crop. For potato, late blight is particularly damaging, since it can infect the whole field within two weeks. Losses reach 70% of the crop. Phytophthorosis spreads through mushroom spores, which allows it to quickly move underground and infect the tubers.

In the first days of appearance, late blight appears in the darkening on the leaves. Also on the underside of the sheet appears a white coating. This is the germinating spores of the fungus. They fall down, infecting themselves with the roots and fruits of potatoes. A little later on the tubers appear brown spots.

Fight against late blight

A dangerous fungus requires serious complex measures. So, it is necessary:

• Use potato varieties that are resistant to late blight.
• Select healthy tubers for planting.
• Treat tubers with fungicidal agents.
• Hill when necessary.
• Increase the dose of phosphate-potassium fertilizer.
• Apply fertilizers containing copper, or spraying with a solution of copper sulfate.
• Remove tops before harvesting.

Nematode

The disease "nematode" is caused not by a virus or a bacterium, but by a microscopic worm that parasitizes on a potato. Check the presence of pest easily: if the bushes wither, and their small leaves are uneven or even pale, the nematode is. The bushes become weak, and the roots are shallow. In July, on these roots will appear small balls (with half a millimeter) with small outgrowths. These are female nematodes, if they develop further, they will turn into cysts, which remain in the earth for another 15 years. In the cyst there are about 600 eggs of the worm.

Fighting the Nematode

After the appearance of the nematode, it is necessary to wait at least 6 years before re-seeding the site. However, there are other ways.

Potatoes of early or unstable nematode varieties are placed in boxes in one layer, poured peat crumb and planted after 20 days. After 50 days, the harvest is collected, and the site is thoroughly cleaned from the tops. The site itself is planted with beans or corn. This will clear the soil of the worm by about 70%.

If rye is sown on the plot, this will also significantly reduce the population of the parasite.

It should be noted that the potato attracts the nematode more than other plants.

Scab

The most common after late blight is the disease of potato - scab. It degrades the quality, marketable appearance of tubers and reduces the level of starch in them by almost 30%. Yields are almost halved. During storage, the infected tubers are very prone to rot.

The causative agent of the scab is mold - a radiant fungus. In potatoes, it penetrates through lenticles and mechanical damage, forming on the surface of sores, which merge together and form a cork tissue. On the tubers appears a white coating - the mycelium of the radiant fungus. When dried, they disappear, and the flesh remains almost unchanged.

There are five types of damage:

• Flat . It affects the skin of young tubers, from which the skin hardens.
• Mesh . It covers tubers with a lot of mesh grooves.
• Convex . Appears in the form of depressions, which later become covered with outgrowths.
• Deep . Deep ulcers of different shapes surrounded by ruptured skin. Visible when harvesting potatoes.
• Convex-deep. Set of two types of damage. Obstructures with deep ulcers and ruptured skin.

Pathogens scabs are stored in the ground for several years. They are not affected by negative climatic factors, they persist even in drought and at a temperature of -30 ° C. Hot and dry weather during flowering only contributes to infection.

The source of infection is always soil. Tubers can not infect each other, so they can be stored together.

Fighting the scab

The scab is not easy to spot right away, so it's impossible to save the already infected potatoes. Diseases and pests of other types even "warn" about their appearance, but it is better to fight with all in advance with the help of the following procedures:

• Compliance with crop rotation.
• Cultivation in the area of sideral crops.
• Use of healthy fruits for sowing.
• Application of acidic fertilizers.
• Careful preparation.
• Use of resistant varieties.
• Regular watering during the growing season.

Alternaria

The disease spread everywhere, where potatoes are grown. Diseases and treatment of solanaceous plants are still more studied in the southern regions, since in the south ideal conditions for the growth and spread of fungi, which tolerate alternaria.

Depending on the period, the disease can manifest itself in different ways. Infection begins after rain or dew. Spores of the fungus fall into the cracks, mechanical injuries or natural depressions. The acid begins to separate, from which the stems rot and die. At low temperatures, development is insignificant, but in hot weather the disease has a dangerous effect on the yield. Incubation lasts for up to a week.

The first signs are visible on small plants, up to 20 cm high. Later on, dark brown spots appear on the leaves. With good conditions for development, they can be seen already on the third day. A little later, smoke-gray conidia appear. Damaged parts of plants are fragile and soft.

On the tubers appear squashed dark spots of decay, sometimes even with wrinkles. Eventually, the tubers begin to decay completely, drying and blackening.

Fighting with alternaria

In southern regions, potato diseases and their control require special attention. There are three ways to protect the crop:

1. Agrotechnical . Use only healthy planting material, resistant to disease, observe crop rotation and do not forget that early potato varieties are most prone to infection. The seed material must be heated for the first two weeks at a temperature of up to 20 ° C. During the storage period, make sure that there are no diseased tubers. Alternaria can be transmitted from one fetus to another. Remove the tops in a timely manner, it is better to conduct desiccation with the use of special tools.
2. Biological . Spray the tubers before planting with the preparations "Integral", "Bactofit" or "Planrys".
3. Chemical . Preparations "Ridomil Gold We", "VDG" and "Bravo" will save you from all existing mushrooms, depriving them of comfortable conditions. Before planting, you can also spray the potatoes with the fungicide solution "Maxim".

Potato diseases and their control, as well as other pests, always require special attention. Harvest directly depends on how well all requirements are met. The article is not for nothing that photos of potato diseases are listed, because the enemy must be known in person.